^^^
At one stage in the script development for Ridley Scott's Robin Hood (which was initially going to be titled Nottingham) they had a draft where Robin Hood and the Sheriff of Nottingham were the same person, too. At one point it was said to be more of a Fight Club approach, though, where the Sheriff was chasing himself without realizing it. There was also a version where Robin Hood sees the Sheriff slain in battle and takes his place to impersonate him.

The spec script that first got the project rolling had the Sheriff as the hero and Robin Hood as an ambiguous character who's a murder suspect with a storyline that plays like a kind of period police procedural.